JP2001074382A - Regenerative heat exchanging reactor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a high efficiency regenerative heat exchanging reactor in which the quantity of heat to be discarded can be reduced. SOLUTION: High temperature fluid to be processed discharged from a reactor 1 is introduced through a changeover valve 6 to a regenerative heat exchanger 4 where the temperature of the fluid is lowered by imparting heat to other fluid. Subsequently, it is separated into a production substance, an intermediate production substance and a nonreacted substance by means of a separator 5. The production substance is taken out to the outside of the system and the intermediate production substance and nonreacted substance are transferred through a pump 2 and a changeover valve 7 to a regenerative heat exchanger 3. In the regenerative heat exchanger 3, the intermediate production substance and nonreacted substance are heated again up to the vicinity of reaction temperature by receiving stored heat and transferred to the reactor 1 where they are used for reaction. When the operation is repeated, nonreacted substance and intermediate production substance in high temperature fluid close to the reaction temperature discharged from the reactor 1 are recirculated to the reactor 1 at a temperature close to the reaction temperature.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a melting furnace in the kiln industry for melting glass and metal, a firing furnace in the field of manufacturing cement and ceramics requiring firing, and a petrochemical industry such as petroleum refining. The present invention relates to a regenerative heat exchange reactor such as a fractionating tower.

[0002]

2. Description of the Related Art The kiln furnace industry, which is manufactured in a melting furnace like metals such as glass and steel, the inorganic material industry which requires a sintering process such as cement and ceramics, the petrochemical industry such as petroleum refining, etc. Most areas involve heating, heat transfer, transfer and cooling steps of the fluid material. The fluid material to be processed, which is produced in a reactor such as a melting furnace in the production of glass or a fractionation tower in petroleum refining, is cooled after being taken out of the reactor. The energy is effectively used by collecting and reusing it using an exchanger. Also, the sensible heat of the exhaust gas, unreacted fluid and the like discharged from the reactor is recovered and reused.

[0003] A heat exchanger is a device for transferring heat from one fluid to another fluid across a heat transfer wall, and the fluid on both sides of the heat transfer wall includes gas, condensed vapor, liquid, and boiling liquid. There are various combinations. Generally, a heat transfer device for the purpose of recovering waste heat is called a heat exchanger.Here, a heater for the purpose of heating the low-temperature side fluid, a cooler for the purpose of cooling the high-temperature side fluid, It includes a condenser for condensing the vapor in the case of condensing vapor, an evaporator for evaporating the liquid in the case of a liquid having a low boiling temperature, a heat exchanger for recovering the latent heat of condensation, and the like. Further, the present invention also includes a regenerator used to store the heat of a fluid once and then transfer the stored heat to another fluid. The heat transfer wall is required to have a high thermal conductivity and airtightness, and a metal is used at a low temperature, and a ceramic such as silicon carbide is used at a high temperature.

It is important for the structure of the heat transfer device to have a large heat transfer area with respect to the volume, and a structure called a multi-tube type is most widely used. This is a bundle of a number of heat transfer tubes housed in a cylindrical body, with one fluid passing through the inside of the tube and the other fluid passing between the tube and the body to transfer heat between them. is there. In addition, there are a double tube type in which one heat transfer tube is used, a snake tube type in which one heat transfer tube is a snake tube, and the like. These are the viscosity of the fluid in the manufacturing process of the target substance,
It is selected according to conditions such as pressure, flow rate, fluid temperature and temperature difference.

[0005] After the heat of the fluid to be treated discharged from the reactor is recovered by the heat exchanger, the product of the fluid is taken out of the reaction system, and the unreacted fluid is circulated again to the reactor. The fluid that is transferred and heated in the heat exchanger must be moved from the heat exchanger to a predetermined location and used. For this purpose, the heated fluid needs to be pressurized and pumped, which is usually done with a pump.

[0006]

The temperature of the fluid to be treated, such as glass, steel, cement production, or petroleum refining, is 1000 ° C.
However, when recovering heat from such a high-temperature fluid to be processed using a heat exchanger, the temperature of the fluid to be heated in the heat exchanger is similarly increased to a high temperature. It becomes difficult to use a pump to move the pump from the vessel to a predetermined location, and heat cannot be reused. For this reason, the temperature of the fluid to be heated in the heat exchanger must be lower than that of the fluid to be treated, and the recovered heat can be reduced to a low level such as used for preheating combustion air or fuel gas. It was only used as heat. In such a case, the temperature difference between the high-temperature fluid and the low-temperature fluid increases, so that the heat transfer rate in the heat exchanger is large,
It became difficult to control the fluid on the low temperature side to a predetermined temperature, and the amount of heat to be discarded had to be increased.

After the fluid discharged from the reactor passes through the heat exchanger, unreacted substances and intermediate substances are separated from the products, circulated to the reactor and regenerated in the reactor again for the reaction. In the type reactor, high thermal efficiency can be obtained by maintaining the temperature of the circulating fluid as high as possible, but once the fluid is moved by the pump, it is inevitable that the fluid once cools down.

The present invention can be used effectively even when the temperature of a low-temperature fluid in a heat exchanger is high, the temperature of a circulating fluid can be maintained at a high temperature near the reaction temperature, and the amount of heat to be discarded can be reduced. An object of the present invention is to provide a highly efficient regenerative heat exchange reactor that can be reduced in size.

[0009]

According to the present invention, there is provided a regenerative heat exchange reactor comprising: a reactor for performing processing such as heating and cooling of a fluid substance;
A plurality of heat exchangers arranged in parallel, a switching valve for introducing a fluid to be treated discharged from the reactor into one of the heat exchangers, and a product substance of the fluid to be treated discharged from the reactor. A separator that separates the intermediate product and the unreacted material, a pump that pressurizes and moves the intermediate product and the unreacted material that have been cooled by the heat exchanger, and a pump that pressurizes the intermediate product and the unreacted material. And a switching valve for introduction to the other heat exchanger.

[0010] The high temperature fluid to be treated, which is discharged from the reactor and is near the reaction temperature, first gives heat to the other fluid in one heat exchanger, and the fluid to be treated is pressurized and moved by a pump. After the temperature is lowered to the separator, it is moved to the separator. The fluid to which the heat has been transferred in the heat exchanger remains in the heat exchanger and is heated to a temperature close to the fluid to be treated. At this time, the heat exchanger acts as a so-called regenerator. The product separated in the separator is taken out of the system. Next, the high-temperature fluid to be treated discharged from the reactor is guided to the other heat exchanger by the switching valve, gives heat to the other fluid, and is cooled down. After that, the product is taken out of the system, and the intermediate product and unreacted material are transferred to the heat exchanger used first by the pump. Here, the intermediate product and the unreacted material receive the stored heat, are heated to near the reaction temperature again, are moved to the reactor, and can be subjected to the reaction.

[0011] Thereafter, the high-temperature fluid to be treated discharged from the reactor by the switching valve is appropriately guided to one of the heat exchangers and cooled, and then the intermediate product and the unreacted material separated by the separator are separated. The pressure is increased by the pump, moved to the other heat exchanger, raised to near the reaction temperature, and then moved to the reactor repeatedly. By such an operation, the unreacted substances and intermediate products of the high-temperature fluid to be treated discharged from the reactor can be circulated again to the reactor at a temperature close to the reaction temperature, and the overall apparatus has a high thermal efficiency. Can be obtained. Further, since the generated substance is taken out of the system after the temperature is sufficiently lowered, the amount of heat taken out of the system by the generated substance can be minimized, and there is no heat that is actively discarded.

[0012]

An embodiment of the present invention will be described below with reference to the drawings.

As shown in FIG. 1, this regenerative heat exchange type reactor is intended to obtain a target product by heating a reactant in a reactor 1 and causing a necessary reaction. Two regenerative heat exchangers 3 and 4 are connected in parallel to the reactor 1 via a switching valve 6. Further, a separator 5 for separating the target product and taking it out of the system is provided. Here, as the separator 5, various well-known methods such as using a permeable membrane that selectively permeates the target product or using an adsorbent that selectively adsorbs the target product are appropriately selected. Can be used. The separator 5 is provided with a circulation pump 2 for moving the remaining fluid from which the target product has been separated to the reactor 1 through the switching valve 7 through one of the regenerative heat exchangers 3 and 4 to the reactor 1. I have.

In such a configuration, a reactant is supplied from a lower portion of the reactor 1 maintained at a predetermined temperature, and a necessary reaction is started. The high temperature fluid to be processed, which is generated around the reaction temperature in the reactor 1 and discharged, is a mixture of the target product, the intermediate reactant and the unreacted material. This mixed substance is first supplied to the regenerative heat exchanger 3 by the switching valve 6.
It is led to. In the regenerative heat exchanger 3, the high-temperature mixed substance near the reaction temperature gives heat to other fluids in the regenerative heat exchanger 3, and the mixed substance itself is separated by the separator 5 and circulated by the circulation pump. The temperature is lowered to such an extent that the pressure can be raised at 2. The fluid to which heat has been transferred in the regenerative heat exchanger 3 is heated to near the reaction temperature. The mixed substance is separated in a separator 5 into a product substance and taken out of the system. Here, the temperature of the product is sufficiently lowered, and the heat taken out of the system by the product can be minimized. The remaining intermediate product and unreacted material are pressurized by the circulation pump 2 to be movable. The pressurized intermediate product and unreacted material are supplied to the regenerative heat exchanger 4 by the switching valve 7.
After that, the mixture is introduced into the reactor 1 and again subjected to the reaction. The above is the route indicated by the solid line after the switching valve 6 in FIG. After the mixed substance discharged from the reactor 1 circulates through the above-described route and gives heat to the regenerative heat exchanger 3 within a range where heat can be stored in the regenerative heat exchanger 3,
Next, it is guided to the regenerative heat exchanger 4 by the switching valve 6. In the regenerative heat exchanger 4, the high-temperature mixed substance gives its own heat to another fluid in the regenerative heat exchanger 4, and the mixed substance itself is separated by the separator 5 and pressurized by the circulation pump 2. After the temperature of the mixture has been sufficiently reduced to a value as high as possible, the mixed substance is separated in the separator 5 into product and taken out of the system. The remaining intermediate product and unreacted material are pressurized by the circulation pump 2 to be movable. The fluid to which heat has been transferred in the regenerative heat exchanger 4 is heated to near the reaction temperature. The pressurized intermediate product and unreacted material are led to the regenerative heat exchanger 3 by the switching valve 7. The intermediate product and the unreacted material receive the heat stored in the regenerative heat exchanger 3 and are heated to near the reaction temperature, then introduced into the reactor 1 and subjected to the reaction again. The above is the route indicated by the broken line after the switching valve 6 in FIG.

By repeating the above operation, the unreacted substances and intermediate products of the high temperature fluid to be treated near the reaction temperature discharged from the reactor 1 are circulated again to the reactor 1 at a temperature near the reaction temperature. Therefore, high thermal efficiency can be obtained as a whole device. Further, the amount of heat taken out when the reactants are taken out of the system can be minimized, and no heat is actively discarded.

In the regenerative heat exchangers 3 and 4, the fluid that transfers heat from the fluid to be treated discharged from the reactor 1 may be a gas or a liquid, or may be evaporated or condensed when the temperature is raised or lowered. Is also good. Also, the regenerative heat exchangers 3, 4
May be connected to a heat storage device to circulate a fluid capable of transmitting heat. In this case, the heat conduction speed in the heat transfer walls of the regenerative heat exchangers 3 and 4 increases as the speed of the fluid increases, so that the regenerative heat exchangers 3 and 4 can be downsized and the efficiency can be improved. Become. The regenerative heat exchangers 3 and 4 are provided with detectors such as temperature detecting means for detecting and adjusting the amount of heat stored. The regenerative heat exchangers 3 and 4 are provided with detectors such as temperature detecting means for adjusting the amount of heat given by the fluid to be treated or for adjusting the amount of heat given.

The embodiments of the present invention have been described above. However, the present invention is not limited to the above embodiments, and various modifications may be made within the scope of the present invention described in the appended claims. Can be. For example, by passing the reactants through the regenerative heat exchangers 3 and 4 before being introduced into the reactor 1, the reactants can be heated before the reaction, and the energy efficiency in the reactor 1 can be increased. In addition, by installing three or more regenerative heat exchangers in parallel and creating three or more circulation routes, the amount of heat that can be stored in the regenerative heat exchangers can be increased, and the equipment can be operated stably. can do. A heat exchanger is installed inside or on the outer periphery of the reactor 1, and the heat transferred to the regenerative heat exchangers 3 and 4 is circulated through the heat exchanger to supply heat required for the reaction. Is possible.

[0018]

As described above, the regenerative heat exchange type reactor of the present invention has a plurality of regenerative heat exchangers in parallel.
Unreacted substances and intermediate products of the high-temperature fluid to be treated near the reaction temperature discharged from the reactor are cooled down by one regenerative heat exchanger and then returned to near the reaction temperature by the other regenerative heat exchanger. The temperature can be raised and circulated to the reactor, and high thermal efficiency can be obtained as a whole of the apparatus. Further, the amount of heat taken out when the reactants are taken out of the system can be minimized, so that there is no heat that must be positively discarded.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of one embodiment of a regenerative heat exchange reactor of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Reactor 2 ... Circulation pump 3,4 ... Regenerative heat exchanger 5 ... Separator 6,7 ... Switching valve

Claims (1)

[Claims] 1. A reactor for performing a process such as heating and cooling of a fluid substance, a heat exchanger for transferring heat of a fluid to be treated discharged from the reactor to another fluid, and the reaction of the fluid from the heat exchanger In a regenerative heat exchange reactor comprising a circulating pump for circulating in a reactor, a plurality of heat exchangers are installed in parallel, and the heat of the fluid to be treated from the reactor is stored in one of the heat exchangers. After lowering the temperature, the circulation pump pressurizes the fluid by the circulation pump, sends the fluid to the other heat exchanger, raises the temperature by the heat stored in the heat exchanger, and then circulates the fluid through the reactor. A regenerative heat exchange reactor.